docs: def plane_fit(points):
      """
      This fits an n-dimensional plane to a set of points. See
      http://stackoverflow.com/questions/12299540/plane-fitting-to-4-or-more-xyz-points
  
      :parameter points:
          An instance of :class:~numpy.ndarray. The number of columns must be
          equal to three.
      :return:
           A point on the plane and the normal to the plane.
      """
      points = numpy.transpose(points)
      points = numpy.reshape(points, (numpy.shape(points)[0], -1))
      assert points.shape[0] < points.shape[1], points.shape
      ctr = points.mean(axis=1)
      x = points - ctr[:, None]
      M = numpy.dot(x, x.T)
      return ctr, numpy.linalg.svd(M)[0][:, -1]